The uncharacteristic outburst came on Catalan radio when Messi was asked about comments from Javier Faus, the vice president in charge of club finances, who said earlier this month that he saw no reason to change Messi's contract, which runs until 2018.
Messi denied asking for a new deal, but said Faus did not understand what he was talking about.
"Mr. Faus is a person that doesn't know anything about football and wants to run Barcelona like a business, which it isn't," Messi told Catalan radio RAC1 in comments reported by Marca. "Barcelona is the best team in the world and deserves to be represented by the best executives.
"I remind him that neither I nor any of my representatives have asked for a contract extension at any moment, and he knows that very well."
Messi, a four-time world player of the year, is in Argentina recovering from a hamstring injury.